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#pragma once
#include "StateGraph.h"
#include "Core/API/ComputeStateObject.h"
#include "Core/Program/ComputeProgram.h"

namespace Falcor
{
    class ComputeVars;

    /** Compute state.
        This class contains the entire state required by a single dispatch call. It's not an immutable object - you can change it dynamically during rendering.
        The recommended way to use it is to create multiple ComputeState objects (ideally, a single object per program)
    */
    class dlldecl ComputeState
    {
    public:
        using SharedPtr = std::shared_ptr<ComputeState>;
        using SharedConstPtr = std::shared_ptr<const ComputeState>;
        ~ComputeState() = default;

        /** Create a new state object.
            \return A new object, or an exception is thrown if creation failed.
        */
        static SharedPtr create() { return SharedPtr(new ComputeState()); }

        /** Copy constructor. Useful if you need to make minor changes to an already existing object
        */
        SharedPtr operator=(const SharedPtr& other);

        /** Bind a program to the pipeline
        */
        ComputeState& setProgram(const ComputeProgram::SharedPtr& pProgram) { mpProgram = pProgram; return *this; }

        /** Get the currently bound program
        */
        ComputeProgram::SharedPtr getProgram() const { return mpProgram; }

        /** Get the active compute state object
        */
        ComputeStateObject::SharedPtr getCSO(const ComputeVars* pVars);
        
    private:
        ComputeState();
        ComputeProgram::SharedPtr mpProgram;
        ComputeStateObject::Desc mDesc;

        struct CachedData
        {
            const ProgramKernels* pProgramKernels = nullptr;
            const RootSignature* pRootSig = nullptr;
        };
        CachedData mCachedData;

        using StateGraph = StateGraph<ComputeStateObject::SharedPtr, void*>;
        StateGraph::SharedPtr mpCsoGraph;
    };
}
